Quite often in the field of industrial automation and manufacturing, within a given factory or plant, a technician or engineer is typically entrusted to oversee the operation of one or more production lines and repair any process-related problems that might result. Such ability invariably requires a high level of skill. Likewise, whenever a problem does occur, whether major or minor, it is typically necessary to halt operation on said production line, carry out a thorough or cursory examination of the situation, apply a workaround or long-term solution, and restart the production line once again. This often requires considerable investments of time, effort, and money.
In many cases, the nature of the products created on the production line whose operation is interrupted in this way is such that resuming the manufacture of such “partially-formed” products may not be done easily or at all following interruption on such a line, even if the original problem was fully resolved. Thus, in such cases, the products being manufactured or the operation underway is typically unable to recover, and the entire contents of the system typically need to be emptied, and restarted from scratch. The process engendered by this state of affairs which tolerates no error, pause or downtime, represents an unnecessary overhead of time money and wasted supplies. The cost of such interruption, both direct and indirect, whether in terms of labor, and material waste in such cases, represent not only a strategic and logistical risk but also a significant financial liability to entities overseeing such automated manufacturing.
Industrial automation systems using sequential flow charts (SFCs) which involve programmable logic controllers are known in the art, but these systems typically lack the ability to halt (stop), adjust, resume, or restart an industrial automated assembly line following a malfunction or some other execution sequence interruption, and products that issue from such systems are typically of poor quality, or comparatively more costly to produce because of the costs associated with defective batches. No tolerance as to recovery functionality typically exists in industrial automation mechanisms currently, particularly those based on sequential flow charts (SFCs). Furthermore, SFC-based systems typically have a single initial state from which their execution begins, and this limitation underlies shortcomings involved with working with such systems.
Existing industrial automation systems dispatch explicit instructions to an automation system to bring about a pre-specified end or accomplish a specific result. However, said systems are limited by their own lack of awareness as to either the intrinsic state of the product that they are producing or the result they are intended to bring about. The steps that the system should take are expressed in largely monolithic and sequential steps, subject to an inflexible and predetermined procedure. Consider as an example, a bagel-making operation, a part of whose production, in such systems, be expressed using the following series of steps: “[ . . . ] turn on an oven, insert raw bagel into oven, wait 60 seconds, extract cooked bagel from oven [ . . . ]”.
While in many cases, such a system achieves the result of producing bagels, no deeper information or intelligence about the process is known to the system. No information about the state of doneness is known at any intermediary point between the series of steps enumerated above. In such a scenario, a naïve operator's relative lack of knowledge on the state of doneness of the bagel, combined with his lack of knowledge as to the steps to take should a problem occur, makes continued use of such systems a safety, financial, supply, and operational liability.
One solution to the compound problem described above consists of stopping and resuming operation on such production lines and to do so with little to no time and/or material losses. A further solution would be for a human operator to accomplish this having little specialized knowledge, obviating in many cases higher labor costs and unrecoverable costs of discarded material. A further solution still would be to outfit the manufacturing line with the ability to avoid stopping altogether by anticipating and intelligently mitigating technical or other manufacturing deviations which in the current state of the art would require stopping.
A means by which to adequately manage and operate an industrial automation system which tolerates interruption (a system malfunction, for instance) is desperately needed. A means by which the above-mentioned shortcomings within existing systems may be overcome is described herein.